524
FXUS63 KMQT 132259
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
659 PM EDT Mon Oct 13 2025

.KEY MESSAGES...

- Seasonable temperatures for midweek followed by a warm start
  to the weekend.

- Slight chance of light rain showers Tuesday night. Rain
  chances increase Thursday night into the weekend.

&&

.DISCUSSION...
Issued at 345 PM EDT Mon Oct 13 2025

Afternoon RAP analysis and GOES water vapor imagery show the vigorous
mid level trough and associated surface low pressure over far
northern Ontario, which will lift out over Hudson Bay tonight.
Another mid level longwave trough extends from Alberta down across
the western CONUS. High pressure over the Canadian Prairie and
lingering high pressure over the Gulf of St. Lawrence are beginning
to fill surface ridging back in over the Upper Midwest. Observations
indicate a cold front has marched about halfway across the UP, with
dry weather and clear skies in it`s wake. A wide range of temps are
present. Coolest areas are located underneath the cloud cover far
east as well as over the far west/Keweenaw where onshore flow is
limiting temps in the mid 50s to low 60s. Elsewhere, temps have
reached into the 60s with a few spots reaching low 70s! Not much
further heating is anticipated today outside the south central,
which likely will warm into the mid to upper 60s yet early this
evening prior to frontal passage. Otherwise winds remain a bit
breezy in the Keweenaw, with west gusts up to 20-30 mph into this
evening.

Isolated to scattered light rain showers continue moving east, with
dry weather returning to the entire CWA by tonight as the cold front
finally pushes all the way through. Up to 0.1" is possible far east.
In the wake of the cold front tonight, mostly clear skies and light
northwest 5-15 mph winds are expected; gusts up to 20-25 mph linger
overnight in the Keweenaw and near Lake Superior. The clear skies
and weak cold air advection lowers temps back near normal in the 30s
for the interior and upper 30s to mid 40s at the lakeshores.

High pressure builds over the Upper Great Lakes on Tuesday, becoming
centered overhead on Wednesday as it weakens slightly. Mid level
ridging builds over the central CONUS with a ridge riding shortwave
Tuesday night into Wednesday. Meanwhile, the deep trough upstream
sets up over the Rockies and a series of troughs moves over eastern
Canada. Cooler northerly flow on Tuesday keeps temps slightly colder
than normal with highs only expected in the upper 40s to upper 50s
under partly to mostly cloudy skies. With the shortwave, there
remains about a 25-45% chance for at least 0.01" of rain Tuesday
night. Latest deterministic guidance is unimpressive with much
remaining dry outside the WI/MI state line. The EPS contains the
highest probabilities of precip: 70-80% chance for at least 0.1" of
rain (highest probabilities along the state line) while the GEFS is
about one third that and the GEPS has only 10% along the state line.
Regardless, impacts are not expected. Lows will be in the 30s to mid
40s, coldest interior west. That said, if a drier solution pans out,
less clouds could help cooler temps resolve. Quiet and calm weather
returns on Wednesday with the high pressure now centered overhead.
Highs will be in the 50s across the UP. Expect similar lows
Wednesday night, but with clouds increasing from the southwest,
coldest temps will be interior east instead.

Attention then turns to the deep trough upstream. The mid level
ridge begins to migrate east as the trough lifts out over the
Northern Plains, developing surface low Wednesday night. The high
pressure quickly gives way to the east on Thursday, allowing for a
warm front to re-introduce PoPs to the forecast as the low to the
west lifts toward the Dakotas. The trough begins to quickly pivot
northeast Thursday night through Friday, deepening the surface low
as it lifts to near Lake Winnipeg. Guidance begins to diverge on the
mid level pattern as the shortwave/surface low pair continue
northeast this weekend, but persistent troughing over the region
keeps rain chances in the forecast this weekend (supported also by
marginally cold enough lake surface-850mb delta-Ts for lake effect
precip Saturday night and Sunday). That said, impactful amounts of
rain are unlikely given probabilities of 0.5" struggle to reach 25%.
Otherwise, temps warm back above normal for the first half of the
weekend with spots possibly reaching back into the low to mid 70s on
Friday.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 659 PM EDT Mon Oct 13 2025

VFR conditions continue through tonight and Tuesday as high pressure
moves through the area. Winds become light and northerly late
tonight and continue through Tuesday across the terminals.

&&

.MARINE...
Issued at 345 PM EDT Mon Oct 13 2025

A cold front has crossed most of Lake Superior so far today and will
finish crossing the lake by this evening. West becoming northwest
winds of 15-25 kts are expected through tonight in it`s wake. Gusts
around 30 kts will continue through early this evening over the
north central portion of the lake. North-northwest winds over the
west half of the lake settle below 20 kts Tuesday morning with winds
over the east half following suit by Tuesday night as high pressure
builds in. Winds settle below 15 kts across the lake Tuesday night,
holding through Thursday morning. High pressure quickly gives way on
Thursday, reintroducing 20-30 kt winds to the lake for Thursday
night and next weekend.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.

&&

$$

DISCUSSION...77
AVIATION...TAP
MARINE...77